The present invention relates generally to ovens for baking bread. More particularly, the invention describes an urn-shaped traditional clay oven configured for baking flatbreads on the walls thereof, which is adapted to allow baking bread on the removable plurality of baking trays positioned in the center portion of the oven.
Generally, oval urn-shaped clay ovens have been used for centuries in Asia and on the Indian sub-continent. A vessel of the urn-shaped oven is typically made from earthen ware or fired clay, and has a heat source generally made by burning wood or from charcoal located at the bottom of the vessel. Modem ovens of this type have been adapted to run on a gas supply and so subsequent problems of ash fall out and mess have been avoided—see FIG. 1. As the oven heats up, it becomes a thermal mass and so cooks the food by convection, conduction, and radiation.
Flatbreads such as a Georgian flat bread (“kartuli puri”), Indian flat bread (naan), chapattis and others are baked by being placed on the internal side walls of the oven and are evenly cooked on both surfaces at the same time. This wrap around heat ensures a fast response in baking the flatbread. Because of the oven's innate process of cooking, western style conventional ovens are rendered unsuitable. By virtue of their size, cost and weight these conventional ovens are generally restricted to industrial and commercial operations.
Flatbreads are traditionally made in the Caucuses, Central and South Asia, India and now enjoyed worldwide, especially as an accompaniment to traditional ethnic foods. It is generally made from leavened dough that is flattened and baked in an urn-shaped oven, referred to by various names such as tone or tandoor.
A traditional oven consisted of an oval clay baking layer encased in a masonry or earth housing. An insulating layer of sand may be provided between the clay layer and the housing. The oven may be heated by charcoal or wood burned in the bottom of the baking chamber. Also provided is a cover for the top opening of the oven, which is generally smaller than the largest internal diameter of the oven. The generally oval shape of the vertical cross-section of the oven is critical for proper baking as it causes reflections of radiating heat and assures even baking on both sides of the flatbread.
To bake flatbreads in a traditional oven, pieces of flattened dough are slapped by hand or a baking pad onto an extremely hot interior wall of the oven. A hook may be used to remove the baked bread after a short baking time.
The basic process for baking flatbreads has not changed for centuries. Modern oval ovens use different materials (such as steel housings and ceramic interiors) and different heating options (such as electric heating elements or gas burners). However, the basic shape of the oven, and the vertical wall-based baking process have not changed.
Despite the popularity of flatbreads, a traditional oven design described above has a number of drawbacks—in terms of productivity, material issues and poor safety.
A traditional flatbread must be baked at very high temperatures to impart the sultry smoky characteristic that is its signature. Clay ovens, in particular, are known to crack under prolonged exposure to high heat. Cracks can cause the traditional sand fill that is used to insulate the oven to leak into the baking chamber, potentially getting into the food. It is seldom possible to effectively patch a clay oven once it cracks. Accordingly, it becomes necessary at regular intervals to replace the entire oven.
Traditional baking methods are also dangerous even for skilled operators. The inside of the oven reaches temperatures often in excess of 700° F. In order to slap the raw bread dough onto the inside walls of the oven, the operator must stick a portion of his arm into the oven. Any slight contact with the walls of the oven can result in severe burns. The top openings of the oven are often relatively small (as small as 1-2 ft across in some cases), increasing the difficulty to maneuver the bread into place without contacting the hot oven surfaces.
In a traditional oven, a baker can only bake a small number of flatbread at a time due to the small size of most ovens and due to the quick baking process requiring constant human involvement and attention. Consequently, an operator bakes a steady stream of tiny batches of breads for immediate serving and consumption. For the purposes of a commercial bakery, it is desirable to have an oven that can be utilized for the purposes of baking a traditional flatbread as well as other bread products which are baked using conventional ovens.
The need therefore exists for an oven that can be configured for both purposes: baking flatbreads on its oval sidewalls as well as baking conventional breads and bread products on regular trays as done in a modern bakery. The need also exists for a conversion kit to adapt a traditional flatbread producing urn-shaped oven to baking regular bread and bread products.